Crimping tool having a full stroke compelling means



June 19, 1962 R. J. KOBIELLA CRIMPING TOOL HAVING A FULL STROKE COMPELLING MEANS 2 Sheets-Sheet 1 Filed Feb. 24. 1959 June 19, 1962 R. J. KOBIELLA 3,039,336

CRIMPING TOOL HAVING A FULL STROKE COMPELLING MEANS Filed Feb. 24. 1959 2 Sheets-Sheet 2 INVENTOR.

A TTOR/VE Y5 United States Patent 3,039,336 CRlMPlNG TOOL HAVING A FULL STROKE COMPELLING MEANS Robert J. Kohiella, Rolling Meadows, 11]., assignor to Signode Steel Strapping Company, Chicago, Ill., a corporation of Delaware Filed Feb. 24, 1959, Ser. No. 794,984 12 Claims. (Cl. 81-9.1)

The present invention relates to crimping tools in which the crimping jaws are mounted between a pair of side plates with manual operating handles connected to the jaws for manipulation thereof. More particularly, the invention relates to new and improved structures for insuring that the crimping jaws are moved into their fully closed, crimping position before the operating handles can be oppositely moved to open the jaws and thereby release the crimping tool from the work.

Crimping tools of the type under consideration are well known for the crimping of overlapped strap ends, which may be surrounded by a seal, for the purpose of sealing the strap ends together.

A difiiculty which has been experienced often in the use of this type of tool lies in the fact that a proper seal for strap ends requires that the operator of the tool should manipulate the handles and the jaws of the tool through a full crimping stroke. If the operator removes the tool from the strap ends after only partially completing the crimping stroke, a proper seal will not be effected and the strap ends may separate and release the goods tied or bound by the strap.

A full jaw-closing, crimping stroke is insured in accordance with the present invention, so that the operator of an embodiment of this invention cannot effect only partial crimping of a seal.

An illustrative embodiment of this invention as described in detail below, includes a combination of a toggle-biased latch, a movable operating handle that operates a reciprocating member which coacts with the latch to move the same into a position where the toggle biases the latch into a handle-obstructing position to,

obstruct opposite or jaw-opening movement of the operating handle, and means associated with the movable operating handle and coacting with the latch to move the same into a position where the toggle biases the latch into a handle-releasing position.

The invention will be more fully described in conjunction with the accompanying drawings showing an illustrative embodiment of the invention and in which:

FIG. 1 is a partial side elevation, partly in section, and illustrating a preferered crimping tool constructed in accordance with the invention, the tool being shown with the operating handles in closed position;

FIG. 2 is an end View of the crimping tool shown in FIG. 1;

FIGS. 3, 4 and are diagrammatic partial side elevations showing the operation of the crimping tool of the invention in step-by-step fashion;

FIG. 3 shows the handles in closed position, this position corresponding to the fully closed, crimping position of the crimping jaws;

FIG. 4 shows the operating handles in open position, corresponding to the open or work-releasing position of the crimping jaws; and

FIG. 5 shows the operating handles in partially closed position, corresponding to a position of the crimping jaws in which the work is partly deformed and in which position the crimping jaws encircle the work and cannot be pulled away therefrom.

Referring more particularly to FIG. 1, the crimping tool illustrated comprises apair of side plates and 11 between which are mounted the crimping jaw links 12 and 13, which carry the crimping jaws 12 and 13', these crimping jaw links being mounted for movement between the side plates 10 and 11 in a plane parallel to the plane of the side plates. The term crimping jaw is also employed to designate the combination of crimping jaw link and crimping jaw per se.

Secured to the side plate 11 is a fixed handle mount 14 having a bore 15 within which the fixed handle 16 is secured. The fixed handle mount 14 is desirably formed integral with the side plate 11 as a single casting. The side plate 10 is secured to the side plate 11 and also to the handle mount 14 by means of bolts 17, 18 and 19. Bolt 17 is threaded into the mounting plate 14, as indicated at 17, and bolts 18 and 19 are fastened in place by means of nuts such as the nut 18 shown in FIG. 1.

The invention requires at least one movable handle 20 mounted for pivotal movement. In the embodiment of the invention shown in the drawings, the movable handle 20 moves in a plane perpendicular to the plane of the side plates. A reciprocating member is linked to the movable handle for movement thereby and means link the reciprocating member with the crimping jaws whereby a forward or closing movement of the movable handle will lower the reciprocating member and close the jaws and an opposite or opening movement of the movable handle will elevate the reciprocating member and open the jaws.

The fixed handle 16 provides leverage for operating the movable handle 20 and may be eliminated when the crimping tool is fixed in position as part of a sealing tool in which event the tool body provides the desired leverage.

The fixed handle mount 14 is formed at its upper end with a pair of forwardly extending ears 14' which extend to a positoin above the side plate 10. The movable operating handle 20 is pivoted to the cars 14' of the fixed handle mount 14 by means of pin 21 which is secured in place by lock washer 21'. The movable operating handle 20 carries a link 22 which is pivotally secured at one end to a downward extension 23 of the operating handle 20 and to a reciprocating member 24 at the other end thereof. The movable operating handle 20 is formed with a cam face 20 on the inner side thereof, the purpose of which will be described hereinafter.

The lower end of the reciprocating member 24 is formed as a yoke to provide a pair of downwardly extending legs 25 and 26 through which a pin 27 projects. Reciprocating member 24 may also be termed a crosshead. The pin 27 carries the crimping jaw operating links 28 and 29 which are pivoted at their outer extremities to the crimping jaw links 12 and 13 by the pivotal connections 3%) and 31 respectively. The crimping jaws 12 and 13 are pivoted to the side plates 10 and 11 by the pins 32 and 33.

When the reciprocating member 24 is elevated, the inner end of the links 28 and 29 are elevated drawing the pivots 3t? and 31 inwardly to cause the crimping jaw links 12 and 13 to be pivoted around'pivots 32 and 33 and cause the crimping jaws 12 and 13' to be pulled outwardly into work-releasing position.

Thus, a reciprocating member constituted by crosshead 24 is linked by means of link 22 to the movable handle 20 for movement thereby and means are provided for linking the reciprocating member with the crimping jaws whereby forward or closing movement of handle 20 toward handle 16 will lower the reciprocating member and close the crimping jaws, and opposite or opening movement of handle 20 away from handle 16 will elevate the reciprocating member and open the crimping jaws.

Referring again to FIG. 1, the fixed mounting plate 14 is. formed with flanges or webs 34 which extend upwardly and forwardly of the fixed handle 16. Extending across webs 34 at the lower rearward end thereof is a shoulder portion 35 which is formed with a recess 35 formed with an enlarged mouth in which a spring backing washer 37 is seated. One end of a toggle bolt 38 extends through the washer 37 into the bore 36. The toggle bolt 38 is surrounded by a compression spring 39 which is seated at one end on the washer 37 and at the other end against an outwardly extending flange 40 formed on the toggle bolt 38.

A latch plate 42 is pivotally secured to the interior of the webs 34 of the fixed mounting plate 14 and is mounted for rotation about a central support or pivot pin 41 which is fixed with respect to side plates 19 and 11. The rear end of the latch plate 42 is formed with a tail 43 which is pivotally secured to the forward end of toggle bolt 38 by means of pin 44. It will be observed that pin 44 as shown in FIG. 1 is positioned above and to the right of an imaginary line between the pivot 41 and the bore 36. The intermediate dead center position is on this line. Spring 39 serves to bias tail 43 of latch plate 42 selectively on either side of the intermediate dead center position. In FIG. 1 the parts are shown in what will be seen hereafter to be handle releasing or retracted position in which the latch plate 42 is held in a counterclockwise rotated position.

The reciprocating member or crosshead 24 is formed with a cam face 45 that coacts with the upper inner end of the latch plate 42 which in FIGS. 1 and 3 is positioned in the path of the reciprocating member 24. The cam face 45 coacts with a roller or cam follower 46 rotatably mounted in the upper inner end of the latch plate 42 as'indicated at 47. The protruding end 27 and the upper inner end of the latch plate 42 carrying follower 46 extend through a slot 11' in side wall 11.

When the crosshead 24 is elevated by raising the movable handle 20, the cam face 45 will bear against the follower 46 to cause the upper inner end of the latch plate 42 to move away from the reciprocating member. This rotates the latch plate in a clockwise direction until the tail 43 is moved to position the pin 44 below dead center as the reciprocating member 24 nears its fully elevated position. When pin 44 moves beyond dead center, spring 33 forces the latch plate 42 to rotate in a clockwise direction. The initial rotation of latch plate 42 biases the lower portion of the latch plate toward reciprocating member 24 while the crimping jaws are partly open. The locking corner 4d on the lower inner end of the latch plate 42 abuts the end face of protruding portion 27' of the pivot pin 27 in reciprocating member 24 preventing the latch plate 42 from moving further into a blocking position and permitting the handle 20 and crimping jaws l2 and 13 to be moved to a fully open position. When the handle is lowered and the crimping jaws are moved in a closing direction, the protruding portion 27' of pin 27 will pass below locking corner 48 permitting the latch to be biased by compression spring 39 to a position over the portion, 27 of pin 27 so that a blocking action is thereby achieved.

The invention also includes means associated with the movable handle and positioned in the path of the upper end of the latch plate when the latch plate is in blocking position for returning the latch plate to a position beyond dead center in the opposite direction as the movable handle reachesthe end of its opposite movement corresponding to'a fully closed position of the crimping jaws.

The structure for returning the latch plate in this embodiment of the invention is constituted by the cam face 20' formed on the underside of the head of the movable handle 20. As the handle is moved to a closed position the cam face 20' contacts follower 4s carried by the latch plate 42 and moves the same in retracted direction, counter clockwis as viewed in FIG. 1 until it passes the dead center position.

While the structure of the crimping tool has now been set forth, the invention will be more fully understood from the description of the operation which is presented in conjunction with the step-by-step diagrammatic drawings of FIGS. 3, 4 and 5.

The mechanism is shown in FIG. 3 in a fully closed position. In FIG. 4 the mechanism is fully open and in FIG. 5 the mechanism is partly closed and is shown as moving in a jaw closing direction.

Starting with the mechanism in a fully closed position, arrow A identifies the direction of opposite or opening pivotal movement of the operating handle 20 which functions to open the crimping jaws 12 and 13'. This opposite or opening movement of handle 20 elevates the link 22 which raises the crosshead or reciprocating member 24 and the pivot pin 27 (arrow B). As the crosshead or reciprocating member 24 moves upwardly from the position shown in FIG. 3 to the position shown in FIG. 4, the cam face 45 forming on the reciprocating member 24 engages the follower 46 on the latch plate 42 and causes the latch plate 42 to pivot in a clockwise direction beyond dead center (pin 44 is moved below and to the left of an imaginary line between the pin 41 and the bore 36). As soon as pin 44 passes dead center, the compression toggle spring 39 acts upon the flange 40 of toggle bolt 38 to force the latch plate 42 to rotate still further in a clockwise direction thereby forcing the lower portion of latch plate 42 against the protruding end 27 of pin 27. The movement of the latch plate 42 is indicated by arrow C in FIG. 4.

When the crimping tool is in the position shown in FIG. 4 with the handle 20 in its fully elevated position and the crimping jaws opened, the tool may be positioned with the crimping jaws disposed about the overlapped strap ends and seal member to be crimped together so that the movable handle 20 may be moved forwardly or downwardly to cause the crimping jaws to close thereabout and thereby effect the desired crimping and sealing operation.

FIG. 5 shows the handle 2%) in its partially closed position, the partial closing movement being indicated by the arrow D. During the closing or forward movement of handle 20, the link 22 is lowered thereby also lowering the crosshead or reciprocating member 24 and the pivot pin 27 (note arrow B). As the pivot pin 27 is lowered, the crimping jaws close about the work and protruding end 27 of pin 27 moves beneath the locking corner 48 of the latch plate 42, thus freeing the latch plate 42 for further clockwise rotation as indicated by arrow F. This further rotation is effected by the action of the toggle compression spring 39 which, together with toggle bolt 38 freely mounted in bore 36 provides a constant biasing force tending to rotate latch plate 42 away fro-m its dead center position. It will be observed that the locking corner 48 of the latch plate 42 has now been moved into a position overlying the locking pin 27 and more particularly into the path of the protruding portion 27 of the locking pin 27. The handle 20 cannot be elevated or moved in an opposite direction to cause the crimping jaws to release the work because an opening or opposite movement of handle 20 must be accompanied by an elevation of reciprocating member 24 and locking pin 27 and such elevation is prevented because of the blocking action provided by the locking corner 48 of the latch plate 42 acting against the top of protruding portion 27 of pin 27.

When the handle 20 is moved forwardly to it fully closed position to complete the crimping stroke, as shown in PEG. 3, the cam face 2t) on the movable handle 25) contacts the follower 46 and moves the roller 46 downwardly as the follower 46 rolls along the cam face 20' thereby pivoting the latch plate 42 in a counter-clockwise direction to a position beyond dead center. The spring 39 coacts with the flange 40 of the toggle bolt 38 to rotate the latch plate 42 in a counter-clockwise direction into a retracted position in which the locking corner 48 of the latch plate 42 is clear of the protruding end 27 of the pivot pin 27. In this manner, the handle 20 is freed for jaw opening or releasing movement. Accordingly, when the crimping stroke has been completed the handle 20 is free for opening movement as indicated in FIG. 4 whereby the crimping jaws may be opened and the work released.

Thus, when a crimping tool embodying the present invention is employed to crimp overlapped strap ends to seal the same, the tool cannot be released from the work until the crimping operation has been completed. Prior to completion of the crimping operation the jaws are interengaged with the work, due to partial crimping thereof, and they cannot be opened due to engagement of the latch plate 42 and the pin 27.

It will be understood that the specific structure which has been illustrated annd described constitutes a preferred, illustrative construction in accordance with the invention and that many variations in specific structure can be made without departing from the present invention. Thus, as an example, the protruding end 27 of pivot pin 27 is not essential and this structure can be replaced by a suitable projecting portion formed on the reciprocating member 24 and reference to a protruding portion on the reciprocating member is intended to include the protruding end 27 of pivot pin 27. Further, the cam face 45 may be replaced by other means associated with the reciprocating member 24 or the link 22 or even the pivot pin 27 to engage the upper extremity of the latch plate 42 in order to pivot the same in a clockwise direction during the upward movement of the reciprocating member 24. Still further, the roller 46 may be eliminated and the handle 20 made to act directly upon the'latch plate 42 or a slide plate may be substituted for the roller 46. As will be evident also, the cam face 20 on the operating handle 29 may be eliminated and any other suitable means employed for pivoting the latch plate 42 in a counter-clockwise direction when the handle 20 is moved forwardly into its lowermost position. Similarly, while a toggle and compression spring combination seated within a bore in the mounting plate 14 has been described as a preferred illustration for constantly rotationally biasing the latch plate away from an intermediate dead cented position, it will be appreciated that many other biasing structures providing the same function may be used. For example, the latch plate may be formed with a wedge cam surface and a spring-biased roller-follower may bear against the cam surface to cause the latch plate to be pivoted away from a dead center position in which the roller contacts the apex of the cam.

I claim:

1. A crimping tool comprising a pair of side plates, a movable handle mounted for pivotal movement with respect to said side plates, a pair of crimping jaws positioned between said sid'eplates and movable in a plane parallel to said side plates between an open work-re ceiving position and a closed crimping position, a reciprocating member linked to said movable handle for movement thereby, means linking said reciprocating member with said crimping jaws whereby forward movement of said movable handle will lower said reciprocating member and close said jaws, and opposite movement of said movable handle will elevate said' reciprocating member and open said jaws, a latch plate mounted at a pivot point for pivotal movement with respect to said side plates and rotational biasing means pivotally associated with said latch plate at one end and substantially fixed at its other end, the line between the pivot point of the latch plate and the substantially fixed end of said biasing means being an intermediate dead center line, said rotational biasing means being disposed to rotationally bias the lower outer end of said latch plate away from said intermediate dead center line between the pivot point of the latch plate and the substantially fixed end of said biasing means, the upper inner end of said latch plate being positioned in alignment with the path of said reciprocating member such that elevation of said reciprocating member will move the lower inner end of said latch plate toward said reciprocating member to a position away from said dead center line when said reciprocating member nears its fully elevated position and whereby said biasing means will rotate said latch plate and bias the lower portion of said latch plate toward said reciprocating member when said crimping jaws are partly open, said reciprocating member having a protruding portion which is contacted by the lower inner portion of said latch plate when said latch plate is initially rotated to prevent re-opening of the tool during initial closure of the jaws.

2. A crimping tool comprising a pair of side plates, a movable handle mounted for pivotal movement with respect to said side plates, a pair of crimping jaws positioned between said side plates and movable in a plane parallel to said side plates between an open work-receiving position and a closed crimping position, a reciprocating member linked to said movable handle for movement thereby, means linking said reciprocating member with said crimping jaws whereby forward movement of said movable handle will lower said reciprocating member and close said jaws, and opposite movement of said movable handle will elevate said reciprocating member and open said jaws, a latch plate mounted at a pivot point for pivotal movement with respect to said side plates, and rotational biasing means associated with said latch plate at one end and substantially fixed at its other end, the line between the pivot point of the latch plate and said substantially fixed end of said biasing means being an intermediate dead center line, said rotational biasing means being disposed to rotatably bias the lower outer end of said latch plate away from said intermediate dead center line between the pivot point of the latch plate and the substantially fixed end of said biasing means, the upper inner end of said latch plate being positioned in alignment with the path of said reciprocating member such that elevation of said reciprocating member will move the lower inner end of said latch plate toward said reciprocating member to a position away from said dead center line when said reciprocating member nears its fully elevated position and whereby said biasing means will rotate said latch plate and bias the lower portion of said latch plate toward said reciprocating member when said crimping jaws are partly open, said reciprocating member having a protruding portion which is contacted by the lower portion of said latch plate when said latch plate is initially rotated, said latch plate being formed with a locking corner at the lower inner end thereof so thatwhen said protruding portion of said reciprocating member moves below said locking corner while said crimping jaws are closing, said biasing means Will further rotate said latch plate to cause said locking corner to overlie said protruding portion and block elevation of said reciprocating member to thereby prevent an opposite movement of said movable handle and prevent opening of the partially closed crimping jaws.

3. A crimping tool comprising a pair of side plates, a movable handle mounted for pivotal movement with respect to said side plates, a pair of crimping jaws positioned between said side plates and movable in a plane parallel to said side plates between an open work-receiving position and a closed crimping position, a reciprocating member linked to said movable handle for movement thereby, means linking said reciprocating member with said crimping jaws whereby forward movement of said movable handle will lower said reciprocating member and close said jaws, and opposite movement of said movable handle will elevate said reciprocating member and open said jaws, a latch plate mounted at a pivot point for pivotal movement with respect to said side plates, rotational biasing means associated with said latch plate at one end and substantially fixed at its other end, the line between the pivot point of the latch plate and said substantially fixed end of said biasing means being an intermediate dead center line, said rotational biasing means being disposed to rotatably bias the lower outer end of said latch plate away from said intermediate dead center line between the pivot point of the latch plate and the substantially fixed end of said biasing means, the upper inner end of said latch plate being positioned in alignment with the path of said reciprocating member so that elevation of said reciprocating member will move the lower inner end of said latch plate toward said reciprocating member to a position away from said dead center line when said reciprocating member nears its fully elevated position and whereby said biasing means will rotate said latch plate and bias the lower portion of said latch plate toward said reciprocating member when said crimping jaws are partly open, said reciprocating member having a protruding portion which is contacted by the lower inner portion of said latch plate when said latch plate is initially rotated, said latch plate being formed with a locking corner at the lower inner end thereof so that when said protruding portion of said reciprocating member moves below said locking corner while said crimping jaws are closing, said biasing means will further rotate said latch plate to cause said locking corner to overlie said protruding portion and block elevation of said reciprocating member to thereby prevent an opposite movement of said movable handle and prevent opening of the partially closed crimping jaws, and means associated with said movable handle and positioned in the path of the upper end of said latch plate when said latch plate is in blocking position for returning said latch plate in the opposite direction as said movable handle reaches the end of its opposite movement corresponding to a fully closed position of said crimping jaws.

4. A crimping tool as recited in claim 3 in which said means linking said reciprocating member with said crimping jaws includes a pivot pin extending through said reciprocating member, the end of said pivot pin protruding through said reciprocating member constituting the protruding portion of said reciprocating member.

5. A crimping tool as recited in claim 3 in which said means for constantly rotationally biasing said latch plate away from an intermediate dead center position comprises a toggle bolt pivoted to the lower end of said latch plate and a compression spring biasing said bolt toward said latch plate.

6. A crimping tool as recited in claim 3 in which said latch plate carries a roller at the upper inner end thereof and said reciprocating member is formed with an inclined cam face which engages said roller to rotate said latch plate.

7. A crimping tool as recited in claim 3 in which said means for returning said latch plate in the opposite direction includes a cam face surface disposed on the underside of said movable handle, said cam face engaging the upper inner end of said latch plate to lower the same as said movable handle is moved forwardly to closed position.

8. A crimping tool as recited in claim 7 in which said latch plate carries a roller at the upper inner end thereof, said roller engaging said cam face on the underside of said movable handle.

9. The apparatus of claim 3 wherein said tool includes a fixed handle secured to one of said side plates, said fixed handle being disposed in the plane of rotation of said pivotally movable handle, and one side plate including a mount comprising forwardly extending ears overlying the 53 other of said side plates and a web extending upwardly and forwardly of said fixed handle, said movable handle being pivoted to said ears, said latch plate being mounted on said web.

10. A crimping tool as recited in claim 9 in which said web is formed with a shoulder portion defining a bore at the lower rearward end thereof, and said rotational biasing means comprises a toggle bolt freely mounted in said bore at one end thereof and pivoted to the lower end of said latch plate at the other end thereof and a compression spring seated adjacent said bore and biasing said bolt away from said shoulder whereby the point of interconnection between said bolt and said latch plate is constantly biased to move in a direction away from a line joining said bore with the point of securement of said latch plate with said web.

11. The apparatus of claim 3 wherein said tool includes a fixed handle secured to one of said side plates, said side plate further comprising an integral handle mount including a web extending upwardly and forwardly of said fixed handle, said latch plate being mounted on said web, said web being formed with a shoulder portion at the lower rearward end thereof, said shoulder having a bore therein disposed substantially in alignment with said latch, and said rotational means comprises a toggle bolt freely mounted in said bore at one end thereof and pivoted to the lower end of said latch plate at the other end thereof and a compression spring seated adjacent said bore and biasing said bolt away from said shoulder whereby the point of interconnection between said bolt and said latch plate is constantly biased to move in a direction away from a line joining said bore with the point of securement of said latch plate with said web.

12. In a crimping tool having a fixed handle, a movabel handle, and mechanism disposed to perform a crimping operation upon movement of said movable handle with respect to said fixed handle; means to provide full jaw-closing of said tool to prevent partial crimping of a seal, said full jaw-closing means comprising a reciprocating member responsive to movement of said movable handle to provide jaw-closing and jaw-opening, a movable latch, said latch being cooperatively arranged with said reciprocating member to obstruct movement of said reciprocating member in one position of said latch, and to be disengaged from said reciprocating member in another position of said latch, and toggle means to bias said latch toward either said obstructing position or said disengaging position, said toggle means comprising a toggle member having a flat head and a shaft portion, said fiat head being pivotally attached to said latch, said fixed handle having means fixedly secured thereto, said secured means having a recess therein, said shaft of said toggle having an end thereof disposed in said recess, said recess diameter being larger than the diameter of said shaft to enable pivoting of said shaft in said recess, and a coiled spring disposed on said shaft to form a supported resilient means to bias said latch, said toggle being aligned with said latch for movement of said latch to said disengaging position when said movable handle is moved to a fully closed position.

References Cited in the file of this patent UNITED STATES PATENTS 2,831,380 Falck-Pedersen Apr. 22, 1958 2,833,170 Pachter May 6, 1958 2,855,813 Hepler Oct. 14, 1958 

